Pore-Scale Redistribution of Water during Wetting of Air-Dried Soils As Studied by Low-Field NMR Relaxometry

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• 作者：Tiona R. Todoruk ; Cooper H. Langford ; and Apostolos Kantzas
• 刊名：Environmental Science & Technology
• 出版年：2003
• 出版时间：June 15, 2003
• 年：2003
• 卷：37
• 期：12
• 页码：2707 - 2713
• 全文大小：165K
• 年卷期：v.37,no.12(June 15, 2003)
• ISSN：1520-5851

文摘

The kinetics of water uptake and redistribution in severalsoils and their components are studied using NMRrelaxometry. Unlike the normal behavior observed instable porous media, entry into micropores in the soil is aslow process as compared to entry into macro- andmesopores. This indicates that soils air-dried at ambienttemperature include gel phases that have collapsed orreoriented, closing micropores, during drying. Wetting mustthen include the swelling processes that re-openmicropores. This can even exhibit temperature dependencegiving an "apparent activation energy" comparable tothat of a chemical reaction, for example, ester hydrolysis.The processes of micropore opening may play a role inslow uptake of contaminants into soils.